The invention described herein relates to separators for separating fluids of different densities and especially to gas separators, i.e., a separator for separating the liquid and gaseous phases encountered in oil and water wells and of the type associated with a submersible motor-pump assembly.
It has long been a practice to use a submersible motor-pump assembly in a well casing of a water or oil well to pump well fluid from the well. In many instances, substantial quantities of gaseous substances are present in the well fluid which can adversely affect the pumping operation if permitted to enter the pump of the assembly. In extreme situations, excessive quantities of gas or excessive expansion of a gaseous phase will cause "gas lock" which completely restricts the flow of the well fluid, i.e., oil or water. When "gas lock" occurs, the pump must be shut down for later restart. The necessary procedure can be costly and time consuming. A common practice in the industry is to incorporate a gas separator in the motor-pump assembly, the separator being located in advance of the pump inlet. Ideally, the separator reduces the occurance of "gas lock" and permits the motor-pump to operate continuously and efficiently.
Examples of gas separators are shown in U.S. Pat. Nos. 2,311,963; 3,291,057; 3,300,950; 3,624,822 3,867,056; and 3,887,342. While at least some of the patented structures have been effective to reduce "gas lock", the efficiency of gas removal may be somewhat questionable and, in any, event, can be improved.